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Spec Mammalia: Xenarthra
INTRODUCTION & HISTORY Xenarthrans evolved in South America, and this continent has been their traditional home, although some have migrated into North America. Although these creatures did not radiate into arboreal insectivore niches as in RL (these niches already having been taken by the didelphids), they became quite succsessful as insectivorous ground-dwellers and burrowers. INSECTIPHAGIDAE (Pangodilloes and nufflers ) Spec's 'anteaters' are the dominant small insectivores of South America, and are clearly xenarthrans, possessing the clade's slow-growing, enamel-less teeth and xenarthrual articulation between their vertebrae (although insectiphags' backs are more flexible than other xenarthrans. However, these hedgehog like creatures are not true myrmecophagids (the familiar anteaters of our home timeline), but a more generalized family that often mimics the pholidotes (pangolins) of RL. Pangodillo (Echinomanis echinis) The first mammalogists to explore Spec's Panamanian Isthmus were startled to discover the pangodillo (Echinomanis echinis) a creature that at first glance appeared to be a pangolin - a scaled anteater-like mammal. Not only did the creature possess razor-sharp bladelike 'spikes' instead of the flat but very tough scales of the homeworld pangolins, its mere existence in the New World, and simply existing, was a major puzzle. In our home timeline the Pholidota are exclusively of Old World in distribution, and are not found in South America, nor are they even xenarthrans, but instead relatives of carnivorans. On top of that, the branch of Mammalia that lead to the pangolins had, as far as paleontologists could determine, never existed on Spec. Bristly Nuffler (Notechinogale minor) Nufflers are common, but cryptic, insectivorous denizens of the undergrowth of the south american scrub. The bristly nuffler, found in the drier Amazon region, is the smallest and most common species, the size of a kitten. Adorned with stiff bristly hairs that can sometimes break the skin, even more often they irritate the mouths of a would-be predator. The clade Notechinogale consists of numerous species of "bristly nufflers", though they are relatively conservative in their differences. Spiny Nuffler (Dendrechinogale scansor) The spiny nuffler climbs more often than its smaller relatives, and frequently grows to the size of a sut, which it resembles in behavior and diet. It has sharp spines on its back, deterring strigosaurs and other predators. A denizen of the Amazon rainforest, this animal is in many ways transitional between the bristly nufflers and the pangodillo. CHLAMYPHORIDAE (Major Armadillos and kin) The most diverse group of xenarthrans, armadillos are small generalist/insectivores that range from central South America to southern North America. Many species (though not all) are covered with an articulating armor of flattened plates. All armadillos are burrowers to some extent. Armatell (Carnodasypodis horridus) The armatell is a large (almost a metre long in some regions) burrowing, nocturnal carnivore. The species has an excellent sense of smell, which this badger-like animal uses locate its prey of small mammals an reptiles. Prey is usually unearthed with the digging claws on the forefeet, and dispatched with a swift bite. Armatell teeth are, like those of other xenarthrans, naked dentine, but much sharper and more robust than those of its kin. These teeth grow slowly, but are strongly rooted in the gums and remain throughout the predator's life. In fact, armatell lifespan is intimately linked with that of their teeth, as a toothless animal soon starves. Armatells dig extensive burrows ('sets') that many other species will inhabit if abandoned, but are not social. Younger individuals may inherit a set, but only after the current resident dies or is driven away BULIIDAE (Bullids) Bullids are small and (not surprisingly) bullet-shaped burrowers that range from Argentina to Brazil. The family sports armadillo-like armor, but this plating has been reduced to a carapace over the top of the skull - used to push earth aside as they burrow - and scattered bony nodules over the shoulders. Bullids are adapted to eat colonial insects - termites and ants - which they dispatch by burrowing under the insects' nests and then bursting into the upper chambers from below. Many species of termite defend against this behavior by spitting poisons at attacking bullids, and by extending the hard walls of their fortresses far below ground level, but the sharp claws and impervious head shield of the little insectivores are proof against the strongest wall or poison. Swarming ants, which seek to escape predators by leaving their nests and forming large, mobile bivouacs, are not safe from bullids, either, as the these xenarthrans will often construct conical traps, in the manner of an ant-lion, in which they can catch swarms of walking prey. Argentinian bullid (Bulia argentiniensis) With their hard head shields and in their general shape, bullids resemble South America's other diggers, the docodont moliarties. Bullids, however, are easily distinguishable from their primitive lookalikes in the construction of their head shields (which are fused hair, not horn), their erect posture, and the number of digging claws on their hands (four, not five). Bullids also feed primarily upon termites an ants, while docodonts eat worms and other burrowing invertebrates, and so species of both groups may dwell in the same land, even going so far as to share burrows, but of the two, bullids are far more likely to be seen on or near ground surface than the more secretive docodonts. Argentinean bullids are small burrowing insectivores, thriving on (or rather, under) the South American pampas. This species is rarely seen on the surface, and has small eyes and ears - the latter protected by small, bony, hornlike extensions of the 'skullcap'. These horns are slightly larger in the males, but do not appear to be used in any offensive function. Arbourarmour (Hoplotamandua recurvonychus) One of the most unusual inhabitants of the Amazon rainforest is the arbourarmour. This large-clawed, rat-sized bullette has a prehensile tail and is an extraordinarily good climber and swimmer. Unlike its relatives, it has pursued a lifestyle similar to the “true” armadillos, albeit with caveats. When the rainy season hits the Amazon, this animal undergoes a niche change. Its claw sheaths lengthen very quickly in the weeks preceding the rains, during which the keratin growth on the carapace slows; when the rains come, it transforms from a low-level forager to a climbing inhabitant of the treetops. The evolution of this incredible trophic transformation has allowed this animal's ancestors passage into the seasonally flooded Amazon basin, where their ground-dwelling cousins could not. The prehensile tail is equal or greater in dexterity to that of the tamandua of our timeline, the tail morphology of which is paralleled in the arbourarmour. PARADASYPODIDAE (Armies) This clade seems to encompass many of the more traditional armadillos of Spec; their resemblance, though in many ways strikingly similar to armadillos, is superficial, as the scute arrangement and internal anatomy shows. These are examples of the more mundane armadillos that inhabit the Americas of Spec. Both grow no larger than a small cat. Top is the knuckleball (Bolotherium hoploscutatum), a common insectivore of the pampas capable of curling into an impenetrable ball. It is well named; its rounded, rivet-like scutes are the thickest of any armadillo. Below is the common army (Paradasypus populator), known to be widespread throughout South America, north through to warm-temperate North America. Mongoose army ( Dolichodasypus herpestoides ) On the South American pampas of Home-Earth, one will occasionally see an armadillo trundle slowly from place to place. But in the pampas of Spec, the mongoose army (Dolichodasypus herpestoides) is far from slow and cumbersome, in spite of its armour. Cat-sized, and far sleeker in shape than most other xenarthrans, it still carries trunk armour as protection against cazadins. Its diet consists of practically any small animal it can find, though it has a penchant for reptiles. Like the far heavier armatell, it digs "sets" in which to sleep and raise young. Its dentition is unique, showing differentiation from thin conical teeth at the front, to rounded teeth further back in the jaw line. BABELTHERIDEANS As xenarthrans go, these mammals are bizarre. They possess many typical xenarthrans traits, such as a lack of enameling to their teeth, bone scutes embedded within their skin and the xenarthrales, the complex assortment of flexible articulations within the vertebrate joints. The xenarthran trend towards bipedality is also present, to an extreme degree. Babeltherideans also possess the strange "septomaxilla", lacking in all other therians. Here the similarities end. The babeltherideans have developed a complex pelvis, with the ischium and acetabelum extended to a great degree. The ilium flares broadly. Both seem to be responses to massive leg muscle insertions. The tail is long and like HE macropods, supports further extensions of femur muscles at its base. The subdermal bone scutes that tend to be randomly placed among non-Cingulata xenarthrans are instead highly organized along the dorsal sacrum and torso, extending across the base of the tail. The guts also possess rows of tightly ligmented subnormal bone scutes. Both ligmentized scute complexes serve the purpose of keeping the body rigid during intensive activity. The resulting union allows babeltherideans to do something perhaps truly unique among synapsids. They can walk and run bipedally just like a dinosaur. The babeltherideans have one of the most intriguing digestive arraignments of any mammals. They possess a multichambered stomach, secondarily simplified in the itavykais. Their lack of enamel allows them to retain perpetually ever growing teeth. The digestive "flora" includes bacteria, fungi, and even nematode worms that are secondarily consumed much like HE macropods. The teeth are heavily derived from a herbivorous or possibly myrmecophagous(?) ancestor. They are secondarily incisorforme, molariforme and most unusually of all, plagiaulacoforme. Babeltherideans seem to have derivatively evolved the ability to see into the ultra-violet spectrum. Both bastardsloths and itavykais possess patterned coats that shine under black lights. Why this ability evolved is not certain. Perhaps the overwhelming presence of ultraviolet patterned predators in Spec in the form of dinosaurs was responsible. Secondarily derived fur markings could've been selected sexually over time. As alwaysyet further research is needed. SCHIZICEBIDAE (Itavykais or Tarziwaks) These are heavily derived babeltherideans. Their closest ecological analogs may be the galagos of HE. Quite small, averaging less than half a meter including the tail and just .5 to 1.5 kilos, these primarily carnivorous babeltherideans also partake of saps and nectar when in season. Insects and microvertebrates are preferred food samples. Resting camouflaged against tree trunk or within wood burrows, they spend the day asleep. Night awakens them to possibilities of predation. Itavykais range from the dry subtropical forests of Mexico to the open woodlands bordering the pampas. Itavykais are solitary, with a male sharing territory with up to four females at a time. Their secretive nocturnal behavior has made them very hard subjects for research. It is known that females generally have an average of two young per year by the resident male. The offspring remain with the mother for a year before dispersing. Unlike their bastardsloths cousins, their stomachs have simplified, much reduced anterior chambers. Itavykais have a pair of prominent plagiaulacoid teeth in the lower jaws that seem to act in concert with two pairs of molariforme teeth in the upper jaws. The incisorforme teeth number roughly around 7 pairs per jaw. The outer most "incisors" are rather canineforme in appearance, used for seizing insect and small vertebrate prey. The tooth formula follows as thus. It should be recognized that this formula is being used for animals not representative of standard mammalian dentition. PL represents the plagiaulacoid. Upper Jaw I7, PL0, M11 Lower Jaw I7, PL1, M9 The plagiaulacoid is used for shearing through tough chitinous exoskeletons in arthropods and the bony skeletons of vertebrates. The incisors are fairly prominent, though not recognizable so in living specimens, covered as they are with lips. They tear out grooves in sweet sap trees throughout an itavykais' home range. The molariforme teeth are set within a simplified shearing pattern to further process animal matter. Socially, itavykais are mostly loners. Males maintain territories within up to 6 females divide for their own use. Juveniles roaming away from their mothers may remain for up to two years before reaching sexual maturity and seeking out new territories far from their natal home ranges. Daytime sleeping holes usually are utilized by the resident male, females and their offspring. Occasionally, the resident male may share his sleeping hole with many of his weaned offspring. The earliest itavykai fossils known are less than 40,000 years old, indicating they have always been tropical rainforest and dry forest specialists. Molecular and morphological evidence indicates that itavykais split off from the bastardsloths no later than the Oligocene. Llorona (Schizicebus phasmatis) A ghostly white furred itavykai that is renown for its wailing calls akin to a bereaved woman. Scientists camping in the atlantic rainforest region will often see these fearless xenarthran bush babies leaping or walking about on their hind legs grabbing insects attracted to the warmth and light of the fires. Lloronas are simply carrying out an extension of their natural behavior in this respect. They are often seen congregated around herds of sleeping neohadrosaurs or pachamas during the nighttime hours. Lloronas also maintain more typical itavykai dietary habits. They leap from tree limb to limb catching insects with their excellent eyesight and good hearing. Daylight hours has them curled up within tree holes, often with several mates. NOTHUSASIMIADAE (Bastardsloths) These are familiar mammals throughout the Americas. Bodily, bastardsloths resemble the viriosaurs they share their ancestral homeland tropics with. Several key differences exist. Bastardsloths have powerful forelimbs with large claws for digging into soil and climbing up trees. They are of course furred with prominent ears. Whereas viriosaurs are obligate bipeds, bastardsloths are facultative bipeds. Most bastardsloths amble along on all four limbs searching for food. They usually rear up and run on their hind limbs in response to a predatory attack. Small species race to the nearest trees to climb up into for protection. Larger species may seek out burrows or dense undergrowth to lose the predators. The giant species may stand their ground within a circle or against trees or rocks and brandish their claws. Bastardsloths tend to herding species that are rather diurnal in habits. Herd structures may be variant from open mobs where unrelated individuals loosely join and leave at anytime to male led family groups of many females and their offspring in various stages of maturity. Herds may range from less than a dozen to upwards of hundreds in some species. Most bastardsloths are small animals between 5 to 20 kilos in weight. Species found in the cold forests and plains may be much larger. Bastardsloths generally have four digits on their hind limbs, with the 2nd and 3rd digits bearing the primary weight. The forelimbs generally have five digits, with all five bearing fairly robust claws akin to badgers or coatis. Females generally bear 2 to 4 well-developed offspring at a time after a gestation of roughly four to nine months depending on the species. Weaning usually takes place some four months afterwards, with the young stay with their mother for up to a year. Bastardsloths have a fairly extensive fossil record within South America. The first recognizable bastardsloths is a late Eocene mandible coming from an animal just a meter in length and perhaps 8 kilos in weight. The fossils remain rather small, but common until the late Pliocene, when size shoots up. Interestingly the earliest North American bastardsloths show up in the Miocene. They are quite close morphologically to virtually all modern day bastardsloths. This similarity posits the intriguing speculation that the Pliocene Bolide event wiped out the majority of bastardsloths in South America. The only modern day bastardsloth with closer similarities to the pre-Pliocene animals is the trunk-lip. Bastardsloths have molariform teeth very similar to glyptodonts, their cousins on HE. Roughly 8 to 12 molars in each jaw row are present. They also have a pair of plagiaulacoid teeth in the lower jaws buttressing the anterior molars. Incisors are known, with an average of two per jaw row. The trunk lip seems to have lost these, indeed, most South American bastardsloths before the Pliocene were in the process of losing or had lost them. LABIOMANAE (Trunk Lip) These bastardsloths are an ancient line that separated from the main body as far back as the Oligocene. They are montane dwellers, preferring the high scree ringing altiplanos all along the Andean chain. Their size is quite impressive, with adult males reaching up to 200 kilos. The most unusual feature of these bastardsloths is of course, their muzzle. Trunk lips possess massive jaws that have many insertions for lip muscles. The trunk is quite dexterous, akin to a tapir’s though located on the lower jaw instead of being formed from the upper naris and labia. Trunk Lip (Labiomanus morrisi) The sole surviving species is Labiomanus morrisi. Trunk lips feed on tubers and browse scrubs within home ranges of roughly a few square miles or so. Both sexes lead solitary lives. Females share their territory with their young for roughly a year after birth. NOTHUSASIMIANAE (Bastardsloths) The bastardsloths are among the most wide ranging groups of xenarthrans in the Americas. They can be found virtually in every time of environment except the most open stretches of the arctotitan steppes of boreal north america. Bastardsloths have very diverse feeding strategies. Some are browsers, others rooters or grazers. Many employ all three. Size range is also quite diverse, with some species under 10 kilos but most species in the 50 to 150 kilo range and one pampas/altiplanos species reaching close to 500 kilos, rivaling many of the local maniraptorans and the glory elk. Total species numbers are not yet known, with an estimated 30 or so species to eventually be named across the Americas. Bastardsloths are so named because the first sighting of one elicited a cursing response at yet another weird mammal clade in Spec with no clear parallel. Bastardsloths are most diverse in North America, where they seem to have filled in the niche of hogbirds and dinoceratopsians as small pig/tapir like rooters and browsers. However, all bastardsloths under 50 kilos routinely climb trees to forage for leaves and fungi. Carnivorous behavior is rare, though they will occasionally scavenging carcasses or abandoned eggs. Three genera are recognized, Nothusasimius, Eunothusasimius and Improceritherium. Pataguari (Nothusasimius grandis) The largest of the bastardsloths, the pataguari lives in immense herds numbering in the hundreds ambling across the pampas and altiplanos. They forage for grasses and forbs and scrape up shallow tubers and roots. When saber tyrants or other predators threaten, they rear up on their hind legs and thunder across the landscape until either they have outrun the threat or one of their number has fallen prey. They often graze in mixed association with spelks, un-gulates and nandrakes. Pine Bastardsloth (Eunothusasimius pinus) This species of bastardsloth lives in small herds of roughly 12 related females and a single dominant male. These 40 kilo animals are quite arboreal, foraging for conifer needles and fungi throughout their range. They also dig up subterranean fungi, roots and tubers as well as browse twigs from angiosperm and gingko trees found in the understory or clearings. Pine bastardsloths experience winter torpor, with herds sleeping for weeks at a time in caves and dens dug out for the harsh conditions. The 2 rarely 3 or 4 offspring are born communally when spring arrives. When foraging, predators cause them to race up the nearest tree. However, only the most foolish drak would attempt to enter the sleeping burrows of a pinebastardsloth family. Those great claws are very effective at ripping flesh and breaking bones. Little Bastardsloth (Improceritherium brasiliensis) These were the first described bastardsloths although not the only known species at the time. A dweller of the Amazon basin, they live in loose associations of roughly 6 to 12 with interchangeable membership. The flooding season sees them stranded on highland, where they become more vulnerable to fellow marooned predators like ocelotars and cockatrices. ,=Insectiphagidae=Echinomanis echinis (Pangodillo) =Xenarthra=| | ,=Dasypodidae=Carnodasypodis horridus (Armatell) `=| `=Buliidae=Bulia argentiniensis (Argentinian bullid) Category:Animals Category:Mammals Category:Xenarthrans Category:Alternative evolution Category:Spec Dinosauria Category:South America Category:North America Category:Carnivores Category:Central America